PHOENIX — Mets manager Terry Collins made a curious lineup decision before tonight’s game against the Arizona Diamondbacks. With a vacancy in right field, he wavered between new arrival Mike Baxter and Scott Hairston, the hot-swinging bench star. The night before, Hairston had roped a double to open the ninth inning. Collins liked that, and wanted that reassurance on the bench.

So he elected to start Baxter in right. He does not believe Baxter is ready to contribute as a pinch-hitter in late-game situations. Hairston can perform that job.

“I’ve got a situation where be it left-handed or right-handed, I’ve got the guy over there that I know I can put in,” Collins said inside the visiting managers’ office at Chase Field. “Instead of trying to throw it into the basket of a young player who hasn’t done much.”

In just 130 plate appearances, Hairston is actually tied for fourth on the team with seven home runs. He has an .856 on-base plus slugging percentage as well.

“This guy has got nothing but huge hits off the bench,” Collins said. “You put him in big situations, and he has gotten big hits. I’ve told him many times that I know everybody likes to play, but it’s nice to have that piece of the puzzle that over there that you can insert when you need a big hit.”

Plus, Collins said, it wouldn’t hurt to see what Baxter was capable of doing.

“I’ve got to get him in to find out what it takes to let him play here a little bit more,” he said. “So that he can be a useful piece. If I just sit him on the bench night after night after night and don’t get him in there, it’s pretty hard for me to expect him to do much.”

Collins plans to start second baseman Justin Turner on Sunday. Turner has had the past two games off to rest a variety of ailments, including a problem with his right hip flexor. Collins has been forced to use Willie Harris, who is nominally an outfielder, due to the injury to Daniel Murphy and Ruben Tejada’s place at shortstop.

Turner was available to pinch hit both nights. He will also sit at least once during the upcoming series against San Diego.

On Friday night, Mets starter Dillon Gee broke the left hand of Arizona’s Xavier Nady with a fastball. Nady, a former Met, was put on the disabled list and is expected to be out for at least a month. In his place, the Diamondbacks signed Lyle Overbay, who was released by the Pittsburgh Pirates earlier this summer.